[Locke1689]

It's layman writing. The worm uses RSA and RC4. SHA1 or MD6 as a hash. Designing these would obviously take a very skilled cryptographer (actually many, many cryptographers). Implementing it just requires a smart programmer who knows a decent amount about cryptography.

[edmccaffrey]

And deploying it only requires someone who can import a library and follow instructions.

[Locke1689]

Eh, not really. If you were talking about a fully defined cryptographic protocol like SSL I would say you were right, but if you're talking about actual cryptographic implementation I would say that it requires a little more knowledge.

See tptacek's post about "Typing the letter's A-E-S'" into your code and cperciva's many post about improper use of secure cryptography.